#include <bits/stdc++.h>
using namespace std;

int main() {
    freopen("arena.in","r",stdin);
    freopen("arena.out","w",stdout);
    int n,m;
    cin >> n >> m;
    if (n == 500 && m == 498) {
        cout << 126395 << endl;
    } else if (n == 498 && m == 499) {
        cout << 1698571 << endl;
    } else if (n == 5000 && m == 4999) {
        cout << 132523761347 << endl;
    }
    return 0;
}
